Telecommunications network traffic typically includes many types or classes of traffic, each having its own quality of service (QoS) requirements. Voice data, such as voice of Internet Protocol (VoIP) traffic, for example, values low latency over data integrity, and thus can tolerate dropped packets. Bulk data transfer, on the other hand, values data integrity over latency, and thus can tolerate delays through the network so long as data integrity is ensured. Network operators must continually balance these disparate needs, e.g., by giving VoIP calls a larger proportion of the available bandwidth when needed, and by reclaiming some of that bandwidth for use by bulk data transfer when it is no longer needed for VoIP.
The problem is not just between different types of traffic, such as voice and data; network operators typically provide different levels of QoS to different classes of traffic as well. For example, high-paying subscribers, often referred to as a top tier subscribers, will typically be given priority over lower-tier subscribers who pay less for their subscriptions. For data traffic, a top tier subscriber may have an unlimited data download rate, for example, while lower-tier subscribers have a maximum download rate and/or a maximum data transfer limit per subscription period. For voice traffic, a top-tier subscriber may assigned a higher bit rate voice encoder/decoder (codec) for voice calls, which results in better sound quality, while a lower-tier subscriber may be assigned a lower bit rate (and thus lower bandwidth) codec, which results in poorer sound quality. Thus, network operators must also allocate bandwidth and other network resources among subscribers according to the QoS level of each class of subscriber.
A conventional approach to solving the problem of how to balance the QoS requirements of the many different types and classes of traffic on the telecommunication network includes using rate-based algorithms to regulate network traffic. For example, one class of traffic may be limited to one maximum rate while another class of traffic may be limited to another maximum rate. While this approach has the advantage of being simple, it has the disadvantage that it often results in underutilization of the network, because the static limits imposed on types and classes of traffic do not allow those types and classes of traffic to make use of unused bandwidth even if that excess bandwidth is available at the time, e.g., not being used by the class of traffic for which that bandwidth has been reserved. To counter this effect, network operators are often forced to increase the maximum available bandwidth, i.e., by installing additional lines, links, optical fibers, equipment, and the like, which may have a significant expense.
Thus, there is a need for a more adept approach to balancing the needs of various types and classes of traffic in a telecommunications network. More specifically, there exists a need for regulation of multi-priority traffic in a telecommunications network.